Apparatus for measuring the speed of elongated products



June 9, 1953 c. B. HULL. ET Al. 2,641,715

' APPARATUS FOR MEASURING THE sp1-:ED oF ELONGATED PRoDqcTs FimdAF'eb.A 12,. 1947 K 2 sheets-sheet -1 @hak/es 5, 'HU mm Jgne 9, 1953 c. B. HULL. ETAL APPARATUS FOR MEASURING THE 'SPEED OF ELONGATED PRODUCTS Filed Feb. 12, 1947 Y 2 Sheets-Sheet 2 Iig'. 5.

Am. Mw .m m md m 3m. .a 4 ../../m .WMe/dm g Hw# mw, .ma b C Patented June 9, 1953 APPARATUS vFon MEAsUING THE SPEED 0F ELoNGATED PRODUCTS- Charles B. Hull, University-Heights, and Carl C. Keller, Shaker Heights, Ohio, assignors to United States Steel Corporation, a corporation of New Jersey Application February 12, 1947, serialno. 728,110

This invention relates to a mounting for the photocells, light source and rotary shutter of a speed-measuring system wherein the shutter is driven at a speed proportional to that of a moving element, the speed of which is to be determined. l

The object of the invention is to provide a simple, compact and unitary mounting for the several parts of the system whereby they may be installed immediately adjacent to materialworking means such as a stripmill and yet be protected from injury. The invention is disclosed herein as applied to an yinstallation of--this type and may be used as a gauger to control the mill screws, but is equally adapted to various other forms of apparatus where it is desired `to measure the speed cfa traveling member.

The invention will be more readily understood by reference to the accompanying drawings in which:

Figure 1 is a view in perspective of a portion of a continuous strip mill with shutter carrying portions or detector units of the gauging devices in accordance with the invention applied on both sides of one mill stand;

Figure 2 is a view in plan of the portion of the continuous mill shown in Figure 1;

Figure 3 is an enlarged View in perspective of one of the shutter carrying detector units;

Figure 4 is a View in side elevation of one embodiment of a shutter disc; and

Figure 5 is a View in front elevation of the mounting means for two photocells employed in the shutter carrying means of Figure 3.

In Figures 1 and 2 there is Ashown a portion of a continuous rolling mill for strip to which the speed measuring device ofthe present invention may be applied as an element of the screw-down control system for one or more stands thereof. In the embodiment shown, the first mill stand illustrated, which is of the fourhigh type, designated 2, is designed to have the gauge of the strip 'delivered therefrom automatically controlled by the gauging device. The second mill stand, into which strip 6 is fed after issuing from stand 2, is designated 4. As shown in Figure 2, stands 2 and 4 are ldriven by electric motors 8 and I2, respectively, through reducing gearing Il) and i4. Each mill stand is provided with screw-down equipment, that for mill 2 being designated IB and that for mill 4 being denoted I 8. Each of the rolling mill housings is provided with a vertical screwl bearing upon thev bearing block for the backing-up roll, the screw shown in the upper part of stand 2 in Figure 2 1, 2 Claims. (01.1250-233) being .driven by''motor 22 and that shown inthe lower part of such figure being driven by motor 2l). A conventional 'screw-down control circuit selectively effects separate'operation of either motor 20 or 22 in either the up or downdirection, and also permits the combined operation of -both motors at once in either direction for appreciable distances or for very small gauge correcting distances called` jogging measuringV device of theinvention is connected to this screw-down control, asV will be apparent hereinafter, so as to jog both screw-down motors of one stand up Vor down', as required bythe difference betweenthe speeds of strip entering and leavingthe stand, to` hold the stripl to a y substantiallyconstant gauge as rolled.

'The speed measuring device' is provided with va detector unit 24 mounted on the entering sidev of stand 2, and with a similar unit 26 mounted on the exit side. Each detector unit consists of a base 28 to be mounted on a fixed support, not shown, the inner end of the base carrying an arm 30 pivoted for tilting in a vertical plane about a pivot pin 32. The inner end of arm 30 is provided with a bearing for a shaft 36,

on the end of which is mounted a shutter disc 34. A compression spring 38 is disposed between the inner end of arm 30 and base 28 and exerts an upward force on the former almost equal to the moment of the arm, shaft'and disc.'

disposedY at right angles to thel direction of motion of strip 6 and parallel to the surface of the strip, the shutter disc is frictionally driven by contact with the strip and, because of the lightf ness of the rotating parts 34 and 36, disc 32 will have a rim speed which is exactly the linear speed of the strip. vThe shutter is provided with one or more aperturesfof predetermined angular extent and thus for every revolution ofthe disc the one or more photocells employed in unit 44 will emit a certain number of impulses. With the detecting unit shown in Figure 3, which employs two photocells,-there may be used a disc such as shown in Figure 4. Such disc is provided with one circular slot 46 lying between radii spaced somewhat less than the slot The speedalso lying in line with the light source and the photocells. In the modification shown in Figure 3, the axis of rotation of disc 34 lies midway between photocell mountings 48 and 50, so that for each rotation of the disc each cell emits a voltage impulse, the duration .of such impulse at a given speed of rotation of the `discbeing determined by the angular extent of slot 46. The location and spacing of the photocells employed in the detector unit shown in Figure 3 are more clearly shown in Figure 5, Zwherein the mountings 43 and 50 and the photocells 64 and 65 within them, respectively, are shown located on the same horizontal line, the cells having a distance between their centers which is twice the radial center distance of slot 46.

The impulses generated by detectors 24 and 26 may be amplified by known means and supplied to any desired type of device responsive to the frequency of electrical impulses delivered thereto, for indicating the speeds atr which strip enters and leaves mill stand 2 or for automatically controlling the screw-adjusting motors and 22. Y

We claim:

1. A device for obtainingan indication of the speed of a traveling elongated product comprising a base, a photo-cell mounted thereon, an arm pivoted to said base for tilting movement in a vertical plane, and projecting over the path of the product substantially normal thereto, a shaft journaled in said arm in alinement therewith, a shutter disc `on said shaft adapted vto engage the Vproduct and be driven thereby, a

cantilever arm extending from said base over the path of the product and a light source on said arm adapted to project a beam of light onto said photo-cell through an opening in said disc.

2. A device for obtaining an indication of the speed of a traveling elongated product compris- N ing a base, a photocell mounted thereon, an arm pivoted to said base for tilting movement in a Vertical plane, and projecting over the path of the product substantially normal thereto, a

CHARLES B. HULL. CARL C. KELLER.

References oiteain the Yfue of this patent UNTTED STATES PATENTS Number Name Date 1,450,061 Coblentz Mar. 27, 1923 1,618,757 HoXie Feb. 22, 1927 1,871,404 l Brown Aug. 9, 1932 1,957,681 Thompson May 8, 1934 1,976,355 Mees et al Oct. 9, 1934 2,051,018 Umansky Aug. 11, 1936 2,139,489 Cockrell Dec. 6, 1938 2,151,570 Shoults et al Mar. 21, 1939 2,230,715 Cockrell Feb. 4, 1941 '2,281,954 Rinia May 5, 1942 2,332,573 Hibschman et al. Oct. 26, 1943 2,402,928 Summers June 25, V1946 2,451,971 O-man Oct. 19, 1948 FOREIGN PATENTS Number Country Date 465,406 Great Britain May 3, 1937 

